Folding tower

ABSTRACT

A multi-section folding tower for supporting wind turbines, windmills, power generation, communication, lighting, and measurement machines comprises an upper tower section and a lower tower section pivotally connected at an upper hinge, a lever, and a lower hinge attaching the lower tower section to an anchor foundation not requiring concrete wherein equipment mounted to the top of the tower is accessible by lowering a portion of the tower. The two tower sections and lever are assembled on the ground by connecting the upper and lower sections with a hinge, and the lower tower section is hinged to the tower foundation. The hinged tower sections are raised by first pulling the lower tower section to a vertical position, and a removable installation wheel attached to the tower top enables the lower section to be raised to a vertical position. The upper section is raised to a vertical position by pulling the lever.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 61/396,083 filed on May 21, 2010, titled “FOLDING TOWER,” which is hereby expressly incorporated by reference in its entirety.

BACKGROUND

1. Field

The invention relates to tower support structures and methods for erecting them.

2. Description of the Related Art

Wind power is typically harvested by positioning and holding a wind turbine into the wind at some elevation from the ground, in various types of terrain. To accomplish this, a tower structure standing vertically is used to mount a power producing rotor and nacelle. A wind turbine is typically installed in an area with an uncluttered horizontal view at the hub level, to allow the wind to flow into the blades of the wind turbine with the least air turbulence generated by the surrounding.

Tower structures for wind turbines are constructed to accommodate and withstand the weight of the wind turbine assembly, the wind forces acting on the wind turbine blades and on the tower, the precession forces created by change of direction of the spinning wind turbine blades, the vibrations caused by aerodynamic forces on the blades, and by the wind turbine turning mechanisms. In addition, tower structures for horizontal axis wind turbines are constructed to adapt to methods available for erecting the assemblies. Key tower installation considerations include factors such as safety, damage avoidance to the wind turbine, and limiting installation cost such as that of using a crane and concrete.

Various types of towers have been used in the past to support small wind turbines generating electrical power. Supporting towers for horizontal axis wind turbines may be grouped under three common types, guyed towers, tilt-up towers, and self supporting towers. Tower structures are typically constructed with lattice, truss or tubular assemblies. The tower is typically assembled on the ground prior to starting the erection process.

Guyed towers are typically used for small wind turbines. The guyed tower may be installed with a crane that lifts the assembled tower to a standing position prior to tensing and securing the guy wires. Guyed towers can also be erected one section at a time without the use of a crane, A temporary boom extending beyond the top of the tower is used to lift the next tower sections and finally, the small wind turbine or other top mounted equipment. Guyed towers require wide space access around the base of the tower for anchoring the guy wires.

Tilt-up towers are towers hinged at the ground level and can be lowered to perform maintenance on the equipment installed on top of the tower. Typically, the wind turbine and tower are assembled while the tower lies on the ground at the installation site. The tower is raised using a winch or a heavy vehicle located some distance away from the base of the tower to pull on cables attached to the top of the tower, with a pivoting gin pole transferring the initial horizontal force into a vertical lifting component. Guy cables are often required during the erection process to limit lateral movements of the tower structure.

Self-supporting towers are free-standing structures often pre-assembled on the ground and lifted to the upright position using a crane. The wind turbine may be installed and lifted with the tower, or may be lifted separately and then positioned on top of the tower, Once erected, the tower is typically not lowered again. A built-in ladder provides access to the equipment on top of the tower. Free-standing towers are typically heavier and more expensive.

Though some of the proposed concepts in the above referenced patents and prior art address the need to facilitate construction and erection of the tower and the installation of the wind turbine on top of a tower structure at the installation site, other factors such as tower structure complexity, reliability and need for a large crane need careful review. Raising and lowering of a tower in a harsh environment in typically remotely accessible areas involving snow, ice or dirt build-up on telescoping, sliding and rail type structural elements are technically challenging. Using special external structures or large lifting devices or vehicles add burden and cost to installation operations. In general, tower structures and their erection method for wind turbine applications have evolved by adding complexity to the construction of the tower and lifting system.

Though non-telescopic tilt-up towers facilitate the access to the equipment located at the upper end of the tower structure and do not need a crane for their erection to a standing position, common tilt-up towers involve the pivoting of a lengthy structure with equipment load at its upper end which implies a single lifting maneuver which puts at risk the entire wind turbine and tower assemblies. The use of tilt-up towers is therefore generally limited to small wind turbines.

There have been many attempts to lower the cost of wind turbine towers, but to date none have been commercially successful because it is very difficult to reduce the cost of tilt up guyed single pole or lattice towers, which use a gin pole for tower raising and anchors to secure the guy wires. These towers do not require concrete for the foundation, and typically use a steel plate for the tower base. However, as the size of the turbine grows and the tower height increases, loads increase to a point where raising the tower with a gin pole becomes impractical, and a crane is used to install the tower, and concrete is used for the foundation.

Generally, the best way to reduce the cost of energy, or COE of a wind turbine for towers under 150 feet is to raise the height of the tower. Oversimplified, COE is the ratio of turbine cost to how much energy it produces annually. Higher towers benefit from increased wind speeds, and importantly, smoother wind, which not only allows the turbine to operate more efficiently but also increases its life. Power in the wind increases with the cube of the wind speed increase, and thus increasing tower height from 50 feet to 100 feet will typically result in a power increase of over 50%, but only an approximate 11% increase in the installed cost of the wind turbine. Almost all of this 11% increase is due to a more expensive tower, tower foundation, and tower erection. A key factor in helping wind turbines to become more economically viable in the future will be to raise tower height.

Another trend in the wind turbine industry is a move to larger wind turbines. Larger wind turbines, for both small wind turbines (1 kW-100 kW) and utility class wind turbines (1 MW+) reduces COE. Typically, embodiments disclosed herein will maximize a reduction in COE for small wind turbines from about 5 kW to 100 kW. Below about 5 kW, tower foundations can be designed without concrete, and the towers can be tilted up using a gin pole. Above about 100 kW, the tower top thrust loads produced by large rotors, and their great mass, require the use of concrete for the foundation and a crane during tower installation.

SUMMARY

The systems and methods illustrated and described herein have several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope as expressed by the description that follows, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled “Detailed Description of the Preferred Embodiments” one will understand how the features of the system and methods provide several advantages over traditional systems and methods.

Embodiments disclosed herein incorporate a novel tower design, novel foundation, and installation method. An objective of the embodiments disclosed herein is to lower the installed cost of the tower as well as the cost to access equipment secured to the top of the tower to perform maintenance and repairs, and to be able to lower the equipment to the ground during extreme storms, such as hurricanes and tornados. These embodiments lower the cost of the tower at least three ways: 1. eliminating the need for a crane, 2. eliminating the need for concrete, and 3. reducing the time it takes to raise the tower. In one embodiment a tower is designed to be a tower for wind turbines, which benefit from high towers and require periodic access to the turbine for maintenance.

In one aspect, a folding tower, includes two tower sections, an upper section and a lower section, the upper section being shorter than the lower section. The two tower sections are connected by an upper hinge, which allows the upper section to pivot approximately 180 degrees. A lower hinge connects the lower section to the foundation, which uses anchors in place of concrete to secure the tower to the earth. In some embodiments the anchors are helical anchors, and are screwed into the ground. In some embodiments the folding tower is guyed, and anchors also secure the guy wires. In other embodiments the folding tower does not require guy wires and is self supporting.

The folding tower further incorporates a lever, which in some embodiments is offset from the upper hinge, for raising and lowering the upper section. Offsetting the lever from the hinge increases its mechanical advantage. The folding tower further incorporates a component for securing the upper section to the lower section, which in some embodiments is a latch.

In another aspect, a foundation system for a folding tower having at least three legs includes a plurality of anchors, a centroid absorber, a plurality of force distribution members, a first hinge, and a first leg mount. The anchors include elongated members configured to penetrate into an underlying surface to secure the tower relative to the underlying surface, the plurality of force distribution members extend from the centroid absorber and are configured to distribute forces applied to the tower. The system includes at least one force distribution member for each tower leg and the force distribution members distribute a first portion of said forces to the anchors and a second portion of said forces to the centroid absorber, wherein a sum of the forces to the anchors plus a sum of the first and second portions equals a total force transferred by the tower to the anchors and the absorber. The first hinge is configured to be attached to at least one of the legs of the tower and the first leg mount is attached to one of the force distribution members and disposed between the first hinge and said force distribution member.

In one aspect, a folding tower includes a hinged base portion, an anchor, and a damping system. The hinged based portion is configured to rotate relative to the anchor and the damping system couples the base portion to the anchor. The damping system includes a lever bar, a first energy storing element, and a second energy storing element. The lever bar has a first end and an opposite second end and the base portion and the anchor are coupled to the lever bar near the first end. The first energy storing element is coupled to the lever bar near the second end. The second energy storing element is coupled to the lever bar near the second end and extends from the lever bar in a direction that is generally opposite to a direction that the first energy storing element extends from the lever bar.

In another aspect, a foundation system for a folding tower includes a plurality of damping systems with at least one of the systems comprising a hinged leg mount, a concrete base, and a force distribution system. Each of the damping systems is coupled to the force distribution system and to the concrete base.

In one aspect, a folding tower includes a first portion, a second portion, a pivot, a lever, a boom, and at least one connector. The first portion is configured to rotate relative to the second portion between at least a first position and a second position. The pivot is located between the first portion and the second portion and defines an axis of rotation for the first portion relative to the second portion. The lever includes an elongated structure that is substantially collinear with the first portion. The boom includes an elongated structure that is substantially perpendicular to the first portion. The connector includes a first end and a second end, the first end attached to the first portion and the second end attached to the boom.

In another aspect, a folding tower includes a first portion, a second portion, a pivot, a lever, and a pulley lever. The first portion is configured to rotate relative to the second portion between at least a first position and a second position and the second portion is attached at a first end to an immovable surface. The pivot is located between the first portion and the second portion and defines an axis of rotation for the first portion relative to the second portion. The lever includes an elongated structure that is substantially collinear with the first portion. The pulley lever is attached at a first end to a first end of the lever and the pulley lever can rotate relative to the lever.

In one aspect, a folding tower includes a first pivot, a lower section, a second pivot, and an upper section. The first pivot comprises a first pin defining an axis of rotation of the first pivot. The first pivot also includes a first lower connection and a first upper connection. The first lower and upper connections are rotatable about the axis of rotation and the first pivot is located at least halfway up the folding tower when it is erected. The lower section includes an elongated structure with a first lower end and a second lower end, the first lower end is connected to the first lower connection of the first pivot. The second pivot is connected to the second lower end of the lower section and defines an axis of rotation for the lower section. The second pivot is operably attached to an immovable surface. The upper section includes an elongated structure with a first upper end and a second upper end. The first upper end is connected to the first upper connection of the first pivot and the second upper end defines the top of the folding tower when it is erected. The lower section is enabled to rotate about the axis of rotation of the first pivot and the second pivot. The axis of the second pivot is immovable, the axis of the first pivot is movable, and the during erection of the tower the upper and lower sections are initially in substantially horizontal positions and the first pivot forms an angle relative to the upper and lower sections that is between 129 and 179 degrees.

In another aspect, a method for installing a hinged tower includes providing a tower with a lower section and an upper section rotatably coupled to the lower section, rotating the upper section relative to the lower section such that the upper section extends away from the lower section and such that the upper section and lower sections are substantially collinear, and forming a latch connection between the upper and lower sections by applying tension to a cable to engage a latch mechanism.

In one aspect, a folding tower includes a first pivot, a lower section, a second pivot, an upper section, a first link, a second link, a third link, a fourth link, a first hinge connecting the first link to the second link, a second hinge connecting the second link to the third link, a third hinge connecting the third link to the fourth link, a fourth hinge connecting the fourth link to the first link, a screw, and a nut. The first pivot includes a first pin defining an axis of rotation for the first pivot and also includes a first lower connection and a first upper connection. The first lower and upper connections are rotatable about the axis of rotation and the first pivot is located at least halfway up the folded tower when it is erected. The lower section includes an elongated structure with a first lower end and a second lower end. The first lower end is connected to the first lower connection of the first pivot. The second pivot is connected to the second lower end of the lower section and defines an axis of rotation for the lower section and is operably attached to an immovable surface. The upper section includes an elongated structure with a first upper end and a second upper end. The first upper end is connected to the first upper connection of the first pivot and the second upper end defines the top of the folding tower when it is erected. The first link is fixedly attached to the upper section and the fourth link is fixedly attached to the lower section. The screw is operably attached to the fourth hinge and the nut is operably attached to the second hinge and threaded over the screw. In this aspect, if the screw is fixed the nut can rotate and if the nut is fixed the screw can rotate. The lower section is enabled to rotate about the axis of rotation of the second pivot and the axis of the first pivot can rotate about the axis of rotation of the second pivot and the axis of the second pivot is fixed.

In another aspect, a method of installing a hinged tower includes providing a tower with a lower section that is hinged to an upper section, securing the lower section to a surface, rotating the upper section about the hinge relative to the lower section until the upper section extends away from the lower section and the upper and lower sections are substantially coaxial, and applying tension to a cable member coupled to a latch mechanism, wherein applying tension to the cable member forms a latch connection between the upper section and the lower section.

In one aspect, a folding tower includes a first pivot, a lower section, a second pivot, an upper section, a first link, a second link, a third link, a fourth link, a first hinge connecting the first link to the second link, a second hinge connecting the second link to the third link, a third hinge connecting the third link to the fourth link, a fourth hinge connecting the fourth link to the first link, a screw operably attached to the fourth hinge, and a nut operably attached to the second hinge and threaded over the screw. The first pivot includes a first pin defining an axis of rotation for the first pivot. The first pivot also includes a first lower connection and a first upper connection. The first lower and upper connections are rotatable about the axis of rotation and first pivot is located at least halfway up the folded tower when it is erected. The lower section includes an elongated structure with a first lower end and a second lower end. The first lower end is connected to the first lower connection of the first pivot. The second pivot is connected to the second lower end of the lower section and defines an axis of rotation for the lower section. The second pivot is operably attached to an immovable surface. The upper section includes an elongated structure with a first upper end and a second upper end. The first upper end is connected to the first upper connection of the first pivot and the second upper end defines the top of the folding tower when it is erected. The first link is fixedly attached to the upper section and the fourth link is fixedly attached to the lower section. In this aspect, if the one of the screw or nut is fixed relative to the other, the other can rotate relative to the one of the screw or nut. The lower section is rotatable about the axis of rotation of the second pivot and the axis of the first pivot can rotate about the axis of rotation of the second pivot, and the axis of the second pivot is fixed.

In another aspect, a tower includes an elongated structure including one or more substantially vertical members each having a first end and a second end. The first end of the members defines a base of the tower and the second end of the members is disposed substantially opposite from the first end. The tower also includes a force distribution system having a lever, a force distribution pivot operable attached to the lever, and a rigid structure fixed to a surface. The lever has a first end and a second end. The first end is operably attached to the first end of a member and the second end is operably attached to a force distribution component. The force distribution pivot is attached to the rigid structure and the elongated structure is configured to move relative to the rigid structure.

In one aspect, a tower includes an elongated structure including at least one substantially vertical member having a first end and a second end. The first end of the member comprises a base of the tower and the second end of the member is located substantially vertically about the first end. The tower also includes a force distribution system having at least one lever operably attached to the first end of a member, a force distribution component configured to absorb movement of the lever and operably attached to the lever, a force distribution pivot configured to allow rotation of the lever about the axis of the force distribution pivot and operably attached to the lever, and a rigid structure fixed to the earth and operably attached to the force distribution pivot.

In another aspect, a folding tower includes a first portion, a second portion, and at least one anchor. The anchor is operable to secure the folding tower to a surface and the second portion is hingedly coupled to the anchor such that the second portion is configured to be rotated relative to the surface. The first portion is hingedly coupled to the second portion such that the first portion is configured to be rotated relative to the surface.

In one aspect, a folding tower includes a first portion, a second portion, and a latch mechanism. The first portion is configured to rotate relative to the second portion between at least a first position and a second position and the latch mechanism is configured to inhibit motion of the first portion relative to the second portion when the first portion is in the second position. The latch mechanism includes a first latch plate coupled to the first portion, a second latch plate and comprising a receiving member configured to receive at least a portion of the first latch plate, and a flexible tension member coupled to the first latch plate. The flexible tension member is configured to move the first latch plate relative to the second latch plate.

There exists a need for a tower that is easily erected, without need for a crane or other expensive installation equipment. There also exists a need for a tower where the device mounted at the top of the tower can be accessed without a crane, and where maintenance can be performed without climbing the tower. There exists a need where the top of the tower can be lowered to the ground, and where heavy objects can be removed or mounted to the top of the tower without raising them to the tower top when it is erected. Finally, past solutions to address these problems have been expensive and not commercially successful. There exists a need for an economical solution that solves the aforementioned problems.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an embodiment of a folding tower prior to erection.

FIG. 2 is a side view of the folding tower of FIG. 1 with the lower section vertical.

FIG. 3 is a side view of the folding tower of FIG. 1 with a wind turbine attached to the tower top.

FIG. 4 is a side view of the folding tower of FIG. 1 after erection.

FIG. 5 is a perspective view of an anchor adapter assembly for a hinged leg of the folding tower of FIG. 1.

FIG. 6 is a perspective view of a winch mount assembly for a non-hinged leg of the folding tower of FIG. 1.

FIG. 7 is an exploded view of an anchor adapter assembly for a non-hinged leg of the folding tower of FIG. 1.

FIG. 8 is a perspective view of a latch for the folding tower of FIG. 1 in a closed position.

FIG. 9 is a perspective view of a latch for the folding tower of FIG. 1 in an open position.

FIG. 10 is a line drawing of a side view of an alternative folding tower folded at 10 degrees.

FIG. 11 is a detail view of circle A in FIG. 10.

FIG. 12 is a line drawing of a side view of the folding tower of FIG. 10 folded at 90 degrees.

FIG. 13 is a detail view of circle A in FIG. 12.

FIG. 14 is a line drawing of a side view of the folding tower of FIG. 10 folded at 175 degrees.

FIG. 15 is a detail view of circle A in FIG. 14.

FIG. 16 is a line drawing of a side view of an alternative folding tower folded at 90 degrees.

FIG. 17 is a detail view of circle A in FIG. 16.

FIG. 18 is an exploded view of one embodiment of a latch mechanism and pulley system on a folding tower.

FIG. 19 is a detail view of one embodiment of a damping system on a folding tower.

FIG. 20 is a detail view of one embodiment of a foundation system for a folding tower.

FIG. 21 is an exploded view of a portion of the foundation system of FIG. 20.

FIG. 22 is a perspective view of an embodiment of a foundation system for a folding tower coupled to a portion of a lower half of a folding tower.

FIG. 23 is a perspective view of an embodiment of a pulley lever system coupled to a portion of an upper section of a folding tower.

FIG. 24 is side elevational view of an embodiment of a folding tower system including the foundation of FIG. 22 and the pulley lever system of FIG. 23.

FIG. 25 is a perspective view of the folding tower system of FIG. 24 illustrated with the lower section of the folding tower coupled to the foundation system and in an upright position.

FIG. 26 is a perspective view of an embodiment of a foundation system for a folding tower.

FIG. 27 is a side elevational view of an embodiment of a monopole guyed folding tower illustrated with the lower section of the folding tower extending generally away from the upper section of the folding tower.

FIG. 28 is a side elevational view of the folding tower of FIG. 27 illustrated with the lower section in a generally upright position and the upper section extending at an angle relative to the lower section toward the ground.

FIG. 29 is a side elevation view of the folding tower of FIG. 27 illustrated with a turbine coupled to the upper section of the tower.

FIG. 30 is a perspective view of the folding tower of FIG. 27 illustrated with the upper and lower sections in a raised or upright position and with guy wires attached to the upper and lower sections.

FIG. 31 is a top view of the folding tower and guy wires of FIG. 29.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

Embodiments will now be described with reference to the accompanying figures, wherein like numerals refer to like elements throughout. The terminology used in the description presented herein is not intended to be interpreted in any limited or restrictive manner simply because it is being utilized in conjunction with a detailed description of certain specific embodiments. Furthermore, embodiments disclosed herein may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the embodiments herein described.

The towers described herein are of the folding type that use two hinges, a lower hinge connecting the tower to the foundation, and an upper hinge about halfway up the tower. The upper hinge divides the towers into an upper and lower section.

The folding towers also incorporate a lever to which a flexible tension member, such as a steel cable, is attached. The flexible tension member can be reeled in or out manually or by a machine such as a winch at ground level, to raise and lower the upper section of the tower. The folding towers further incorporate a latch or lock that secures the upper section of the tower to the lower section. The folding towers also incorporate a friction reducer attached to the tower top to minimize the forces required to raise the tower during erection. The folding towers described herein further incorporate a stand or jack to create an angle at the upper hinge that is less than 180 degrees to further minimize the forces. In some embodiments the folding towers use a foundation incorporating anchors.

Referring now to FIG. 1, an embodiment of a folding tower 320 is illustrated in a near horizontal position. In some embodiments the folding tower 320 has three legs 370, while in other embodiments, it may have one, four, five, or six legs. In some embodiments the foundation consists of one or more anchors 360 operably attached to each leg 370. The lower section 390 consists of three legs 370, each of which is attached to one or more anchors 360 comprising the foundation. In some embodiments the anchors 360 are helical anchors, consisting of an anchor shaft 363 with one or more helices 361 attached to the anchor shaft 363. In some embodiments the anchor shaft 363 is a long, slender steel column with the helices 361 welded or bolted to the anchor shaft 363. The helical anchor 360 is screwed into the earth until a certain depth or torque is obtained. In some embodiments the helical anchor 360 can be screwed into the earth with a lever attached to the anchor shaft 363, while in other embodiments the helical anchor 360 is screwed into the earth using machinery, such as an earth auger, skid steer, or backhoe.

Referring now to FIGS. 1, 4, and 5, the anchor adapter assembly 349 is described. FIG. 5 is a close up of the area within circle A on FIG. 4. An anchor adapter 380 is placed over and attached to the helical anchor 360. The anchor adapter 380 in some embodiments consists of a square steel tube that has tabs 374 welded or fastened to it with standard fasteners such as bolts and nuts. An anchor hole 365, located near the top of the helical anchor 360 where it protrudes above the surface of the earth, in some embodiments is a through hole that has an axis perpendicular to the anchor shaft axis. A fastener (not shown), such as a steel pin or bolt is inserted through an adapter hole 376 (which is one or more through holes), through both walls of the anchor adapter 380, and which also goes through the anchor hole 365. In some embodiments the anchor adapter 380 has multiple adapter holes 376 to allow the height of the anchor adapter 380 to be adjusted. A foundation coupler 358, attached to a leg 370, is also attached to the anchor adapter 380. Inserted between the tabs 374 is a foundation boss 382, which in some embodiments is welded to the foundation coupler 358 and is a strong solid steel tab. The foundation boss 382 has a through hole (not shown), and a fastener such as a pin or bolt (not shown) is inserted through a tab hole 378, the foundation boss 382, and in some embodiments a second tab hole 378 to secure the foundation coupler 358 to the anchor adapter 380. This assembly forms a foundation hinge 381, and allows the folding tower 320 to rotate about an axis produced by the tab holes 378. In some embodiments the helical anchors 360 are screwed into the earth parallel with the angled legs 370 of the folding tower 320, and the tabs 374 are bent so that the tab holes 378 create a horizontal axis substantially parallel with the foundation surface. In some embodiments the distance between the tabs 374 is greater than the thickness of the foundation boss 382 to allow for slight differences in the distance between two legs 370 and the distance between two anchor adapters 380. The space between the foundation boss 382 and a tab 374 can be taken up by a slotted shim (not shown), when the fastener, such as a bolt, is secured with a nut, to prevent any lateral or vertical movement of the tower during high winds or earthquakes. In some embodiments the foundation boss 382 can be attached not between two tabs 374 but offset to the side of a tab 374. The bolt in this embodiment is inserted first through the foundation boss 382, then through a first tab 374, and finally a second tab 374. This allows for larger differences in the distance between two legs 370 and the distance between two anchor adapters 380. In some embodiments the tab holes 378 are larger than the bolt to allow for misalignment between the tab holes 378 and the hole in the foundation boss 382. In some embodiments two foundation hinges 381 are used, one for each of two legs 370, and the tab holes 378 larger than the bolt also allow for angular misalignment between the two foundation hinges 381.

Referring now to FIG. 1, two legs 370 of the folding tower 320 can be placed on a stand 364 during assembly of the lower section 390. The lower section 390 of the folding tower 320 is defined as that section below the upper hinge 368 when the folding tower 320 is erected, and during assembly and erection is only attached to the upper section 392 at the two upper hinges 368. The upper section 392 is defined as the section of the folding tower 320 that is generally above the upper hinge 368 when the folding tower 320 is erected and to which the turbine 373 (seen in FIG. 4) is attached, and during assembly and erection is only attached to the lower section 392 at the two upper hinges 368. The lever 338, attached to the upper section 392, extends below the upper hinges 368.

Still referring to FIG. 1, the lower section 390 of the folding tower 320 is described. Two legs 370 are assembled so that a first end of the legs 370 is attached to a foundation coupler 358 slightly above the surface of the earth, and at a second end the legs 370 are attached to the upper hinge A 366. The legs 370 rest on a stand 364 that raises the upper hinges 368 above the surface of the earth. The stand 364 can be a welded metal stand that will support the weight of the folding tower 320, or in some embodiments sawhorses can be used. In other embodiments the stand 364 can be constructed from lumber or wood crisscrossed to create a raised platform upon which the legs 370 can rest. In still other embodiments the stand 364 can be a jack that can raise the tower manually, or it can be raised by using powered equipment such as a hydraulic pump. The purpose of the stand is to create an angle less than 180 degrees at the upper hinge 368 so that the legs 370 of the lower section 390 are not collinear with the upper section legs 393. Reducing the angle produced by the legs 370 relative to the upper section legs 393 lowers the forces required to lift the upper hinge 368 away from the surface of the earth and raise the lower section 390 to a vertical position.

Referring to FIG. 1, a lower section coupler 362 joins sections of the legs 370. In some embodiments the folding tower 320 legs 370 are made from round steel pipe or tubing, while in other embodiments steel angle is used. In still other embodiments a different shape is used, such as square tubing, and the legs 370 are made from aluminum or a lightweight composite. In some embodiments the lower section coupler 362 is made from a steel tube that has an inside diameter slightly larger than the outside diameter of the round tubing or pipe of the legs 370. The steel tube can have a longitudinal slot cut into it and at least two rectangular sections with multiple through holes welded to it so that the lower section coupler 362 can be clamped to secure different leg 370 sections

Still referring to FIG. 1, a short leg 356 comprises the third leg of the lower section 390. The short leg 356 is attached to a lower latch coupler 344, which securely clamps the short leg 356 to the lower section 390. Also attached to the lower latch coupler 344 at a first end are horizontal braces 354, which in the case of a three legged folding tower 320, form a substantially equilateral triangle. At a second end the horizontal braces 354 are attached to one of the legs 370. In some embodiments the horizontal braces 354 are made from steel or aluminum angle, either with equal or unequal leg lengths. In other embodiments the horizontal braces 354 are made from round or square steel or aluminum tubing. The tubing can be perforated with holes so that the horizontal braces 354 can be attached to the lower section 390 using standard fasteners such as bolts and nuts, or welded. In still other embodiments the horizontal braces are made from a lightweight composite. Also attached to the lower latch coupler 344 at a first end are angle braces 346. In some embodiments, to minimize the different types of materials, the angle braces 346 are made from the same material as the horizontal braces 354, although different materials can be used. Both the angle braces 346 and the horizontal braces 354 are attached to the lower latch coupler 344 using standard fasteners such as bolts and nuts or by welding. In some embodiments one or two through holes are made at each end of the horizontal braces 354 and the angle braces 346 and a bolt is inserted through the hole and a corresponding hole in the lower latch coupler 344. At a second end the angle braces 346 are attached to the two upper hinges A 366, preferably using the same method of attachment that is used to attach the first end of the angle braces 346 to the lower latch coupler 344. The upper hinges A 366 in some embodiments secure the legs 370 of the lower section 390 the same way that the lower section coupler 362 secure the legs 370. Also attached to the two upper hinges A 366 is one half of the upper hinge 368. In some embodiments the two upper hinges 368 are formed as a standard hinge, with one or more sections of tubing formed around a pin. Also attached to both upper hinges A 366 is the single horizontal brace 388 (best seen in FIGS. 2, 3, and 4), which is attached at each end using the same method of attachment as the horizontal braces 354. Due to the large forces that the folding tower 320 produces while it is being erected and after it is raised, the upper hinge 368 should be designed with a factor of safety of approximately 1.5-3× greater than the worst case condition to accommodate multiple moments simultaneously acting on different axes.

Still referring to FIG. 1, the upper section 392 is described. The two upper hinges B 372 are attached to the upper hinges A 366 in some embodiments by a pin or bolt inserted through the upper hinges 368, as is typical with conventional hinges. Attached to the upper hinges B 372 are upper section legs 393, using the same method that attaches the legs 370 to the upper hinges A 366. Also attached to the upper hinges B 372 are upper horizontal braces 386, of which there is one for each leg of the folding tower 320. In some embodiments the upper horizontal braces 386 are of the same material and shape as the horizontal braces 354, although the profile may be sized smaller because they are shorter. The upper horizontal braces 386 are attached to the upper hinges B 372 using the same method of attachment as the horizontal braces 354 to the lower section couplers 362. The upper angle braces 384, of which there are two that are a mirror image of each other, are in some embodiments made from the same material as the angle braces 346, and are attached at a first end to the upper hinges B 372 using the same method of attachment as that used to attach the horizontal braces 354 to the lower section couplers 362. The upper angle braces 384 are long, slender members that brace and strengthen the lever 338. In some embodiments the upper angle braces 384 can consist of two pieces attached to each other with standard fasteners such as bolts and nuts. In some embodiments a secondary brace 422, one for each upper angle brace 384, is used to further strengthen and support the lever 338. In some embodiments the secondary brace 422 at a first end is bolted to the upper angle brace 384 using one or two bolts, and at a second end is attached to a lever coupler 336 using the same method of attachment as that used to attach the angle brace 346 to the upper hinge A 366. In some embodiments the lever coupler 336 is similar to the lower section coupler 362, and joins the lever 338 to one of three upper section legs 393. One upper section leg 393 is attached at its first end to the lever coupler 336 and at its second end to the stub tower 328. Stub couplers 332, one for each leg and collinear with the upper section legs 393, are arranged in a substantially equilateral triangle and attach the three upper section legs 393 to the stub tower 328. The stub couplers 332 in some embodiments are welded to the stub plate 330 on a first side, and can be similar to upper hinge B 372 in construction. In some embodiments the stub plate 330 has through holes, to which guy wires or other devices can be attached, such as a pole for an anemometer. On a second side of the stub plate 330 the stub pole 334 is attached, and in some embodiments is welded to the stub plate 330. In other embodiments the stub pole 334 can be attached to the stub plate 330 by fasteners, such as nuts and bolts, and a coupler, similar to the stub couplers 332. In some embodiments the length of the stub pole 334 is slightly longer than the radius of the rotor of the wind turbine 373. At the top of the stub pole 334 in some embodiments are one or more stub holes 322 that provide for attachment of the wind turbine 373 to the stub pole 334. In other embodiments a flange can be attached to the stub pole 334 by welding or by attaching a flange to a coupler similar to the stub coupler 332 so that the folding tower 320 can accommodate different wind turbines 373. In some embodiments a flange can be bolted to the stub pole 334 using the stub holes 322.

Still referring to FIG. 1, erection of the folding tower 320 is described. In some embodiments a friction reducer 326 is temporarily used to minimize the loads required to raise the folding tower 320. The friction reducer 326 can be a wheel, a smooth plastic or teflon pad, or any other low friction material or method. The friction reducer 326 can be temporarily attached to the folding tower 320 with a friction reducing attacher 324. The friction reducing attacher 324, which in some embodiments can be a fork similar to the fork used on the front wheel of a bicycle, can use bolts extending through the stub holes 322 and into corresponding tapped holes in the friction reducing attacher 324. In some embodiments one of the bolts used to attach the friction reducer 326 to the stub pole 334 is an eye bolt that allows a cable (not shown) to be attached to it. In some embodiments a winch (not shown) is attached to the non-hinged anchor 360 that does not have a foundation coupler 358. The winch can be used to pull the stub pole 334 near the top of the folding tower 320 toward the anchors 360 in the direction noted by arrow 333.

Referring now to FIG. 2, the folding tower 320 is shown in a transition stage where it is partially erect. The winch has pulled the stub tower 328 in the direction of arrow 333 so that the upper section 392 is in a substantially vertical position. In some embodiments the friction reducer 326 in this position is blocked or braked using a brake attached to the friction reducer 326, or wood, stone, or concrete blocks, or any other method that can immobilize the friction reducer 326. In some embodiments a flexible tension member (not shown), such as wire rope or steel cable is attached at a first end to the lower latch coupler 344. The flexible tension member at a second end is attached to the winch, or a second winch (not shown), or a vehicle (not shown), such as a truck or construction equipment, to pull the upper section 392 in the direction of arrow 337, which moves the short leg 356 into contact with the non-hinged anchor 360 that is not hinged. The movement of the short leg 356 down into contact with the third anchor 360 that is not hinged simultaneously moves the upper hinge 368 upward in the direction of arrow 335. During the pulling of the stub tower 328 toward the anchors 360, the upper hinge 368 also moved in the direction of arrow 335, which results in the distance between the upper hinge 368 and the surface of the earth to increase. As the upper hinge 368 moves upward, the angle between the legs 370 and the upper leg sections 392 decreases, and the force required to move the stub tower 328 towards the anchors 360 decreases. In some embodiments the folding tower 320 can be braced in the position shown in FIG. 2 by attaching the flexible tension member used to pull the stub tower at its second end to a stationary object, such as the non-hinged anchor, a large tree, rock, or vehicle, that is located in a direction opposite of the winch attached to the non-hinged anchor 360. In this embodiment, the friction reducer 326 can be pulled up a ramp or jacked up to raise the upper hinge 368 and simultaneously lower the short leg 356 into contact with the non-hinged anchor 360.

Referring now to FIGS. 4, 6, and 7, attachment of the short leg 356 to the non-hinged anchor 360 is described. FIGS. 6 and 7 are close up views of circle B on FIG. 4. A winch mount assembly 350 forms attachment locations for the short leg 356, the non-hinged anchor 360, and one or more winches (not shown). An adapter tube 408, with multiple adapter tube holes 410, in some embodiments is a round steel tube with multiple through holes. The adapter tube 408 in some embodiments has an inside diameter that is slightly larger than and fits over the anchor 360. The multiple adapter tube holes 410 allow the height of the winch mount 400 to be adjusted to account for variations in height of both the terrain upon which the folding tower 320 stands and also for differences in height of the non-hinged anchor 360. The adapter tube 408 in some embodiments has a washer welded to its top, to allow insertion of a bolt (not shown) through and from underneath the anchor adapter 408 and through the winch mount 400. A nut (not shown) is used to attach the winch mount 400 to the anchor adapter 408 and also allow the winch mount 400 to rotate on an axis defined by the bolt. In some embodiments one or more winch mount gussets 406 are welded to the winch mount 400. A winch coupler 402, which in some embodiments is a steel L with multiple through holes is attached to the winch mount 400 with bolts and nuts (not shown). In some embodiments steel leg clamps 404 with a curved surface matching the radius of the short leg 356 are placed around the short leg 356 and attached to the winch coupler 402 with bolts and nuts (not shown). The winch mount 400 can be rotated and adjusted both horizontally and vertically to account for misalignment between the position of the short leg 356 and the non-hinged anchor 360. One or more winches (not shown) can be attached to one or more of the unused holes of the winch mount 400.

Referring now to FIGS. 3, 4, 8, and 9, attachment of an apparatus, such as an antenna, meteorological equipment, or wind turbine 373 to the folding tower 320 is described. FIGS. 8 and 9 are close up views of circle C in FIG. 4. The friction reducer 326 is removed from the stub tower 328, and in some embodiments a wind turbine 373 is attached using the same stub holes 322. In some embodiments a flexible tension member (not shown), such as wire rope or a steel cable is attached at a first end to the upper latch plate 416 using conventional cable fittings. The flexible tension member is routed over a pulley 348 attached to the lower latch coupler 344. In some embodiments the pulley 348 is welded to the lower latch coupler 344, while in other embodiments it is attached using standard fasteners, such as bolts and nuts. The pulley 348 guides a flexible tension member attached at its first end to the upper latch plate 416, and to a winch (not shown) attached to the winch mount 350 assembly at its second end, and prevents the flexible tension member from rubbing on the lower latch coupler 344. In some embodiments another flexible tension member (not shown), which can be a steel cable, is attached at a first end to the stub plate 330, and in some embodiments this flexible tension member is also a guy wire. The guy wire can temporarily be attached at a second end to a vehicle, such as a truck or construction equipment, or to another winch, to pull the wind turbine 373 and upper section 392 in the direction of arrow 341. The winch attached to the winch mount 350 can simultaneously be used to reel in the flexible tension member attached to the upper latch plate 416 to pull the lever 338 in the direction of arrow 339. As the upper section 392 rotates around the axis defined by the upper hinge 368, the mechanical advantage produced by the lever 338 increases and the load on the winch decreases. Before the upper section 392 is raised, the stub pole 334 is in an approximately vertical position, or about 90 degrees to the surface of the earth. As the upper section 392 is raised, the guy wire should not be pulled when the angle of the stub pole 334 relative to the surface of the earth is less than 50 degrees. When the stub pole 334 is less than 50 degrees relative to the surface of the earth, the winch has sufficient mechanical advantage to raise the upper section 392 to its upright installed position. In some embodiments, when the upper section 392 is almost to its installed position, the weight of the upper section 392 can cause the lever 338 to fall and the flexible tension member attached to the winch to go slack. To prevent this from occurring, the guy wire can be held taught by the vehicle or second winch, and gently lowered until the upper latch plate 416 contacts the lower latch coupler 344.

Referring to FIGS. 8 and 9, various components of the latch mechanism and associated components are described. Once the upper latch plate 416, a flat steel plate with one or more through holes welded to the upper latch coupler 340, has contacted the lower latch plate 417, another flat steel plate welded to the lower latch coupler 344, the latch arm 342 can be engaged with the latch mount 418. The latch arm 342, which consists of a generally elongated rigid somewhat U shaped component and is made in some embodiments from steel, is attached to the upper latch coupler 340 using bolts or pins which are inserted through latch hinge holes 421. The latch hinge holes 421 are located in approximately the center of the latch arm 342. The latch arm 342 in some embodiments consists of two identical legs which are located one on each side of the upper latch coupler 340. Tapped holes (not shown) located in the upper latch coupler 340 and which are concentric with the latch hinge holes 421, allows the bolts to be screwed into the upper latch coupler 340, attaching the latch arm 342 to the upper latch coupler 340 and allowing it to pivot about the latch hinge holes 421. At a first end of the of the latch arm 342 two latch mounts 420, which in some embodiments are rigid T's, are designed to engage the latch mount 418 after the latch arm 342 has been inserted into the latch slots 442, which are elongated slots in the latch mount 418. In some embodiments the latch mount 418 is a steel U shaped component that is welded to the lower latch coupler 344. The latch arm 342 can be engaged with a flexible tension member (not shown) which in some embodiments is attached at a first end to the latch eyebolt 427, and which can be screwed into a tapped hole (not shown) in the latch mount 418. Pulled by an operator on the ground, the flexible tension member can be attached at a second end to an unused hole on the winch mount assembly 350. The latch arm 342 can be released by an operator on the ground pulling at a first end another flexible tension member (not shown) attached at a second end to the latch release hole 426, located at a second end of the latch arm 342.

Referring now to FIG. 8, in some embodiments the upper latch coupler 340 is a rigid tube with an inside diameter slightly larger than the outside diameter of the tube used to construct the lever 338. The lever 338 is inserted into the upper latch coupler 340 and secured using a bolt or set screw screwed into the latch coupler hole 343. In some embodiments the upper angle braces 384 are attached to the upper latch coupler 340 by bolting them to latch tabs 430 through latch tab holes 432.

In some embodiments the lower latch coupler 344 is a rigid tube with an inside diameter slightly larger than the outside diameter of the tube used to construct the short leg 356. The short leg 356 is inserted into the lower latch coupler 344 and secured using a bolt or set screw screwed into the lower latch hole 440. In some embodiments the angle braces 346 are attached to the lower latch coupler 344 by bolting them to lower latch tabs 438 through lower latch tab holes 436.

Referring now to FIG. 4, the folding tower 320 is shown in its raised position. The upper latch plate 416 has contacted the lower latch plate 417 and the latch arm 342 is in its closed position as shown in FIG. 8.

Referring now to FIG. 10, an alternative folding tower 500 is described. For the purposes of simplicity, only the differences between the folding tower 320 and the folding tower 500 will be described. The folding tower 500 is comprised of an upper section 504 and a lower section 506, and has a wind turbine 502 attached to its top. Attached at the base of the folding tower 500 to the foundation (not shown) is a winch 510, and a flexible tension member 508, such as wire rope, is operably attached to the winch 510. The folding tower 500 is shown with the upper section 504 folded at 10 degrees relative to the lower section 506.

Referring now to FIG. 11, the folding tower 500 is capable of folding at a hinge 538 attaching the upper section 504 to the lower section 506. In some embodiments the folding tower 500 is a three legged tower while in other embodiments it can be a four legged tower. The lower section legs 536 and upper section legs 540 are attached to the hinge 538. In some embodiments there are two hinges 538, with each hinge 538 attached to one of the lower section legs 536 and upper section legs 540. Rigidly attached to the lower section 506 is one or more idler pulleys 544. The directional pulley 544 can be a grooved pulley designed to accommodate wire rope and used for changing the direction of the flexible tension member 508. In some embodiments the directional pulley 544 is comprised of four independent pulleys all concentric and rotating about the same axis, but each of the four pulleys is offset axially and capable of rotating independently. The directional pulley 544 is attached to the lower section 506 with directional bracing 542, 546. In some embodiments the directional bracing 542, 546 is made from steel angle and is bolted with standard fasteners or welded to the lower section 506. Also attached to the lower section 506 is the lower pulley bracing 530, 532 which can also be made from steel angle and bolted with standard fasteners or welded to the lower section 506. Attached to the lower pulley bracing 530 with standard fasteners is an idler pulley 526 which guides the flexible tension member 508 when the folding tower 500 is folded. Also attached to the lower pulley bracing 530, 532 with standard fasteners is the lower pulley 528, which creates a mechanical advantage. Attached to the upper section 504 is the upper pulley bracing 512, 514, which in some embodiments is made from the same materials as the lower pulley bracing 530, 532 and also attached using the same method. A double pulley 516 is attached to the upper pulley bracing 512, 514 using standard fasteners. The double pulley 516 is comprised of two pulleys that are concentric about the same axis but offset axially and capable of independent rotation.

Referring to FIGS. 10 and 11, the flexible tension member 508 travels from the winch 510 to the idler pulley 526, then around one of the pulleys on the double pulley 516, then around the lower pulley 528, then around a second pulley on the double pulley 516, then attached to the termination point 518. The flexible tension member 508 can be attached to the lower section 506 using standard wire rope fasteners.

Referring to FIGS. 12 and 13, the upper section 504 of the folding tower 500 is folded at 90 degrees. The directional pulley 544 is designed so that it clears the upper section leg 548 as the upper section 504 passes over the top of the idler pulley 544. In FIG. 13 it can be seen that a mechanical advantage of four times is provided by the lower pulley 528 and the double pulley 516.

Referring to FIGS. 14 and 15, the upper section 504 of the folding tower 500 is folded at 175 degrees. The four pulleys comprising the directional pulley 544 each contact one section of the flexible tension member 508. Each of the four sections of the flexible tension member 508 in contact with one of the pulleys comprising the directional pulley 544 are axially offset so that they do not contact each other.

Referring to FIGS. 16 and 17, an alternative folding tower 600 is described. For the purposes of simplicity, only the differences between the folding tower 500 and 600 will be described. The folding tower 600 is shown folded at 90 degrees with the upper section 604 horizontal and the lower section 606 vertical. Attached to the upper section 604 is the wind turbine 602. A screw 644 is operably attached to one or more screw hinges 638 using standard fasteners such as bolts and nuts, or it can be welded to the screw hinges 638. In some embodiments the screw 644 is attached to the screw hinges 638 with one or more bearings (not shown) to allow the screw 644 to rotate freely. In some powered applications, a motor (not shown) is attached to the screw hinges 638 and the screw 644 is attached to the motor shaft with a coupler (not shown). The screw 644 is threaded through a nut 618, which is attached by nut hinges 620, 622 to the second link 642 and the third link 646. Link hinge 628 connects the first link 630 to the second link 642 and link hinge 624 connects the third link 646 to the fourth link 626. In some embodiments the screw 644 rotates and the nut 618 is fixed, while in other embodiments the nut 618 rotates and the screw 644 is fixed. In embodiments where the nut 618 rotates a motor (not shown) can be attached to the nut 618. If the nut 618 is rotated, the rotation is converted to linear motion and it will translate along the screw 644 moving closer to the screw hinges 638 if it is rotated in one direction, and farther away from the screw hinges 638 if it is rotated in the opposite direction. This movement can raise the tower 600 from a horizontal position when the first link 630 and second link 642 are nearly parallel. In this position the nut 618 translates so that it moves closer to the screw hinge 638 until the lower section 606 is vertical. After the lower section 606 is secured to the foundation (not shown) and the wind turbine 602 is attached to the top of the tower 600, the nut 618 rotation is reversed and the upper section 604 swings on an axis defined by the screw hinges 638 for 140-180 degrees until the upper section 604 is vertical and the wind turbine 602 is located at the top of the tower 600.

Referring now to FIG. 18, an embodiment of a latch mechanism 700 for use in a folding tower is schematically illustrated. The latch mechanism 700 includes an upper latch plate 716 and a lower latch plate 702. The upper latch plate 716 is coupled to an upper leg portion 728 that extends away from the latch 700. Similarly, the lower latch plate 702 is coupled to a lower leg portion 740 that extends away from the latch 700. The upper and lower latch plates 716, 702 are configured to engage one another forming a latch connection therebetween. When such a latch connection is established, the upper leg portion 728 and the lower leg portion 740 can be aligned to form a continuous tower leg.

As illustrated in FIG. 18, a pulley system 729 can be coupled to the lower leg portion 740. In one embodiment, the pulley system 729 is welded to the lower leg portion 740 at a point near the lower latch plate 702. The pulley system 729 can include a first pulley 736 configured to rotate about a pin 738 and a second pulley 732 configured to rotate about a pin 734. The pins 738, 734 can be disposed between a first plate 730 and a second plate (not shown) and can extend generally parallel to one another such that pulleys 732, 736 lie on planes that are generally parallel to one another. The first plate 730 can include bosses 744, 742 extending toward the second plate to protect the pulleys 732, 736. In one embodiment, pulleys 732, 736 are both disposed on a common plane.

The first and second pulleys 736, 732 can be disposed adjacent to one another and can form a receiving space therebetween to receive a portion of flexible tension member (not shown), for example, a steel cable. The flexible tension member can pass between the pulleys 732, 736, through a slot 712 in the lower latch plate 702, and through aperture 718 in upper latch plate 716. The flexible tension member can be fastened, attached, or otherwise coupled to the upper latch plate 716 such that movement of the flexible tension member can manipulate the upper leg portion 728, and upper portion of the folding tower, about one or more hinges. As the upper leg portion 728 rotates relative to one or more hinges, the flexible tension member can apply pressure to the first or second pulleys 736, 732. In some embodiments, the flexible tension member applies pressure to the second pulley 732 when the upper latch plate 716 is biased away from the lower latch plate 702. In one embodiment, the flexible tension member applies pressure to the second pulley 732 when the upper latch plate is initially biased away from the lower latch plate 702 during reverse erection of the folding tower. In some embodiments, the flexible tension member applies pressure to the first pulley 736 when the upper latch plate 716 is biased towards the lower latch plate 732. In one embodiment, the flexible tension member applies pressure to the first pulley 736 when the upper latch plate 716 rotates past a point where it is vertically positioned above the lower latch plate 702. Thus, the pulley system 729 can be configured to guide a flexible tension member used to manipulate a portion of the folding tower during erection or reverse erection of the folding tower.

Upper latch plate 716 can include a second aperture 722 disposed adjacent to aperture 718. The second aperture 722 can be configured to receive a portion of a safety tension member (not shown), for example, a safety cable, in order to fasten, attach, or otherwise couple the safety tension member to the upper latch plate 716. The safety tension member can extend downward from the upper latch plate 716 through a slot (not shown) in the lower latch plate 702 and may be attached, fastened, or otherwise coupled to the bottom portion of the tower and/or to another structure in order to secure the upper latch plate in a fixed position relative to the lower latch plate. In one embodiment, the safety tension member comprises a steel cable with a ⅝″ diameter that is used to secure the upper latch plate 716 relative to the lower latch plate 702 after a latch connection has been established therebetween.

As illustrated in FIG. 18, the lower latch plate 702 can include a cut-out or recess 708. The upper plate 716 can include a protrusion 724 on the lower side of the plate that has a complimentary shape to the recess 708. In one embodiment, the recess is V-shaped and the protrusion is V-shaped and matches the recess 708. In some embodiments, a vertical shape or surface of the protrusion is complimentary to a vertical shape or surface of the recess such that the shapes are complimentary along more than one plane. A person having ordinary skill in the art will understand that other shapes are possible for the recess 708 and the protrusion 724. For example, the protrusion 724 and recess 708 can both have complimentary curvilinear shapes. When forming a latch connection between the upper plate 716 and the bottom plate 702, the protrusion 724 and the recess 708 can engage one another to guide the upper plate 716 relative to the lower plate 702. The recess 708 can include a tip or flush point 704 that may engage a corresponding point on the protrusion 724 when the upper plate 716 has been properly seated on the lower plate 702. If the protrusion 724 and recess 708 are not initially aligned when the upper plate 716 is brought toward the bottom plate 702, a flexible tension member or cable attached to the upper portion of the folding tower can be used to manipulate the upper plate 716 to align the protrusion and recess.

Still referring to FIG. 18, the lower plate 702 and/or upper plate 716 may include a bearing surface configured to facilitate movement of the plates relative to one another. As illustrated, the lower plate 702 includes a pair of friction reducers or rollers 746, 714 extending therefrom. The rollers 714, 746 can rotate relative to a housing 710 that is attached, fastened, or otherwise coupled to the lower plate 702. In one embodiment, the housing 710 is welded to the lower plate 702. The rollers 714, 746 can be configured to guide the upper plate 716 toward the lower plate 702 during the formation of a latch connection therebetween. In some circumstances, the upper plate 716 is not perfectly aligned in a vertical direction when the upper plate 716 approaches the lower plate 702. In such instances, the rollers 746, 714 can guide the upper plate 716 toward the proper alignment relative to the lower plate 702 and the upper portion of the tower can be manipulated to form a proper latch connection between the upper plate 716 and lower plate 702.

In some embodiments, the lower plate 702 further includes a locking member 706 and a receiving member 720. The receiving member 720 extends from the lower plate 702 away from the lower portion of the tower and forms a receiving space between the receiving member and the lower plate 702. The receiving space is sized and configured to receive a portion of the upper plate 716 when the upper plate 716 is seated on the lower plate 702. Thus, the receiving member 720 limits the movement of the upper plate 716 relative to the lower plate 702 in the vertical direction. In one embodiment, the receiving member 720 includes a lip configured to receive a portion of the upper plate 716 between the lip and the lower plate 702. The locking member 706 can comprise a pin, for example, a spring-loaded pin that can be remotely actuated, and can extend into an aperture 726 formed in the upper plate 716. For illustration purposes, the locking member 706 in FIG. 18 is schematically illustrated in the actuated position. However, the locking member 706 is typically actuated after the upper plate 716 is received by the receiving member 720. In some embodiments, the locking member 706 can be remotely actuated by a cable or similar mechanism. In other embodiments, the locking member 706 can be remotely actuated and can also be remotely retracted into an unactuated position to release the upper plate 716 from the lower plate 702. When the locking member 706 is received within the aperture 726, the locking member limits the movement of the upper plate 716 relative to the lower plate 702 along the plane formed by the juncture of the two plates.

As discussed above, helical anchors, for example, the helical anchors schematically illustrated in FIGS. 1-4, can be used to secure a folding tower relative to the ground. However, folding towers can be subject to high loads, for example, from wind and earthquakes, and can move when subject to such loads. The movement of the folding tower can compact soil so as to create space between the surface of the soil and an installed anchor over time. This can lead to creep and in some circumstances, failure of the anchors. To remedy this situation, anchors having a higher safety factor can be used but this increases the costs of building and installing the tower. As used herein, safety factor refers to a multiplication of the load that a part or structure is required to withstand. Safety factors are higher than design factors (e.g., the load that a part or structure is required to withstand). Thus, an anchor may be required to withstand a load of 20,000 pounds but have a safety factor of 2.0 such that the anchor is configured to withstand a load of 40,000 pounds. As an alternative to more expensive anchors, a damping system can be incorporated in a folding tower between the tower and anchors to lessen the effects of movement of the tower on the anchors.

Referring now to FIG. 19, an embodiment of a damping system 750 is schematically illustrated. The damping system 750 can be incorporated in any of the embodiments of folding towers disclosed herein. In the illustrated embodiment, the damping system 750 is coupled to a vertical leg or member 786 of a folding tower and a horizontal bracing member 784. The damping system 750 includes a lever bar 752 that is generally aligned under a portion of the horizontal bracing member 784. The lever bar 752 can comprise various materials including, for example, metals, composites, organic materials, and polymers. The lever bar 752 can be coupled to a hinge 788 that is coupled to the underside of a vertical leg 786. The hinge 788 can include an upper plate 792 and a lower plate 794. The bottom end of the vertical leg 786 can be coupled to the upper plate 792 of the hinge 788. In one embodiment, a bolt 760 and nut 758 couple the lever bar 752 with the lower plate 794 of the hinge 788. The lever bar 752 can be spaced apart from the hinge 788 by a spacer element 754. On the opposite side of the hinge 788, the lever bar 752 can include a bracket 766 extending therefrom that receives a pivot pin 764. The pivot pin 764 can couple an anchor 762, for example, a helical anchor element, to the lever bar 752. Thus, the lever bar 752 portion of the damping system 750 is disposed between the anchor 762 and the vertical leg 786.

On an end of the lever bar 752 that is opposite from the end of the lever bar 752 that is coupled to the hinge 788, the lever bar 752 can be coupled to a first energy storing element 778 and a second energy storing element 768. In one embodiment, the first and second energy storing elements 768, 778 are springs that are coupled to the lever bar 752 by bolts 782, 770 and washers 772, 776. In one embodiment, the first energy storing element 778 can extend upwardly from the lever bar 752 and the second energy storing element 768 can extend in an opposite direction from the lever bar (e.g., in a downward direction). In one embodiment, the first energy storing element 778 can be disposed between the bracing member 784 and the lever bar 752 and the second energy storing element 768 can be disposed between the lever bar 752 and the surface of the ground that the folding tower rests upon. In this way, the first and second energy storing elements 768, 778 can engage the lever bar 752 therebetween such that movement of the lever bar 752 towards the ground causes the second energy storing element 768 to compress while the first energy storing element 778 goes into tension. Similarly, movement of the lever bar 752 away from the ground causes the first energy storing element 778 to compress while the second energy storing element 768 goes into tension. The opposing compressive and tension forces of the first and second energy storing elements 768, 778 applied to the lever bar 752 can act to absorb and/or dampen energy that is received from the environment and transferred through the folding tower toward the ground before the energy is transferred to the anchors 762. In some embodiments, the first and second energy storing elements 768, 778 are configured to absorber energy only in compression or only in tension. Furthermore, in some embodiments, the lever bar 752 is formed of a flexible energy absorbing material, for example, steel, spring tempered steel, titanium, and high modulus composites such as carbon fiber. The absorption or dampening of energy by the lever bar 752 can further act to dampen energy that is transferred through the folding tower toward the anchors 762. Accordingly, the damping system 750 can act to prevent the disengagement of the anchors 762 from the soil and save costs incurred in the construction and installation of folding towers.

Referring now to FIG. 20, an embodiment of a foundation system 800 for a folding tower (not shown) is schematically illustrated. The foundation system 800 includes a centroid absorber or central damping system 850 and three force distribution systems 802, 804, 806 extending therefrom. Each force distribution system includes 802, 804, 806 a plurality of force distribution members or force absorbing members 808, 810, 812, 814 stacked on top of one another. For example, force distribution system 802 includes a first force absorbing member 808, a second force absorbing member 810 disposed on the first force absorbing member 808, a third force absorbing member 812 disposed on the second force absorbing member 810, and a fourth force absorbing member 814 disposed on the third force absorbing member 812. In some embodiments, the force absorbing members 808, 810, 812, 814 can comprise leaf springs or plates configured to flex when compressive or tensile forces are applied to one or more of the force absorbing members 808, 810, 812, 814. Additionally, the force absorbing members 808, 810, 812, 814 can vary in length. For example, the force absorbing members 808, 810, 812, 814 can decrease in length from the first force absorbing member 808 to the fourth force absorbing member 814. In the illustrated embodiment, each force distribution system 802, 804, 806 includes four force absorbing members 808, 810, 812, 814. However, a person having ordinary skill in the art will understand that a force distribution system can include any number of force absorbing members, for example, one, two, three, four, five, six, seven, eight, nine, or ten. Additionally, a force distribution system may include different types of force absorbing members, for example, leaf springs and plates.

Force distribution system 802 is coupled to an anchor 820 on a first end and to damping system 850 at a second opposite end. The damping system 850 couples the three force distribution systems 802, 804, 806 to a central anchor 894. The first end of the first force absorbing member 808 is coupled or fixedly attached to a bracket 816 that couples the force absorbing member 808 with anchor 820. The bracket 816 includes an aperture 818 that receives a fastener, for example, a threaded fastener, bolt, pin, or screw, to secure the anchor 820 relative to the first force absorbing member 808. Disposed between the first and second ends of the force distribution system 802 is a tower leg mount 832. The tower leg mount 832 can comprise various structures including, for example, a plate or flange. The tower leg mount 832 is configured to engage the bottom of a folding tower leg (not shown) to couple a folding tower to the foundation system 800. As illustrated, each force distribution system 802, 804, 806 includes a leg mount 832 and the leg mounts 832 are aligned with one another such that tower legs (not shown) coupled to the foundation system 800 face a single direction. In some embodiments, one or more of the leg mounts 832 may comprise a hinged plate. For example, the leg mount 834 of force distribution system 806 includes a hinged plate 834 with a hinge tube 836. The hinged plate 834 and hinge tube 836 may coact to hingedly engage a tower leg (not shown) to allow the tower leg to rotate relative to the hinged plate 834 and force distribution system 806. In embodiments where two leg mounts 832 include hinged plates 834 and hinge tubes 836, both hinge plates 834 and hinge tubes 836 may be aligned such that the two hinge structures are coaxially aligned with one another to allow the rotation of the lower portion of the tower about the coaxially aligned hinge tubes 836.

A post or pipe stub 830 and first clamping plate 828 couple the leg mount 832 with the force absorbing members 808, 810, 812, 814. In some embodiments, the leg mount 832 can be clamped or otherwise secured relative to the force absorbing members 808, 810, 812, 814 by securing the first clamping plate 828 relative to a second clamping plate 822 by one or more bolts 826 and nuts 824. For example, in one embodiment, the first and second clamping plates 822, 828 form a clamp structure between the force absorbing members 808, 810, 812, 814 to secure the leg mount to the force distribution system 802.

As discussed above, the movement of a folding tower over time due to high loads can create space between soil and an installed anchor which can lead to anchor failure. Seating a folding tower on a foundation system with one or more force distribution systems can increase the lifetime of the anchor(s) without increasing the cost and/or weight of the anchor(s). In the illustrated embodiment, the force distribution systems 802, 804, 806 can dampen compressive or tensile forces received from tower leg members through the tower leg mounts 832. Additionally, these dampened forces can be transferred to the central damping system 850 to lessen the loads received by the anchors. This foundation system 800 allows for towers to be installed with smaller anchors and allows for the construction of towers with narrow faces (e.g., narrower distances between the bottoms of the legs) because loads from wind and other factors are reduced by the force distribution systems 802, 804, 806 and/or cancelled by the damping system 850.

FIG. 21 schematically illustrates an exploded view of the damping system 850 of FIG. 20. The damping system 850 couples the force distribution systems 802, 804, 806 of the foundation system 800 together to distribute or cancel forces received from a folding tower (not shown) by the force distribution systems 802, 804, 806. That is to say, the damping system 850 receives different compressive or tensile forces applied to the tower and reduced by the force distribution systems 802, 804, 806 and further reduces or cancels out the forces. In other words, the damping system 850 sums the forces applied by the force distribution systems 802, 804, 806 to the damping system 850 to offset the forces that are applied to the outside anchors 816. For example, a folding tower can include three legs with two of the legs in compression due to a received load and the third leg in tension due to the received load. The damping system 850 can receive the forces from the three legs and offset the compressive forces with the tensile force to cancel or reduce the total forces exerted on the foundation system anchors 816 by the tower.

Still referring to FIG. 21, the damping system 850 can include a top plate 856 and a bottom plate 880 configured to clamp or secure the force distribution systems 802, 804, 806 therebetween. The top plate 856 and bottom plate 880 can be secured or otherwise held together using bolts 854 and nuts 882. Spacers 860 may be disposed between the bolts 854 and the top and bottom plates 858, 880 to prevent horizontal movement of the plates 858, 880 or bolts 854 relative to one another. The damping system 850 can also include one or more friction reducing plates 858 disposed between the top plate 856 and the first force distribution system 806. The friction reducing plates 858 can comprise various materials, including for example, plastics, and can be configured to reduce friction between the force distribution systems 802, 804, 806 and to prevent wear on metallic force distribution system components. In some embodiments, the friction reducing plates 858 can be made from a flexible material, for example, rubber that has a friction reducing coating, such as TEFLON. The flexible material can further act to dampen forces transferred from the tower. The first force distribution system 806 can be coupled to the damping system 850 by a slotted bracket 862 disposed at an end of the force distribution system 806. Force distribution system 804 can be secured to force distribution system 806 by the bolts 854 with a plurality of friction reducing plates 864, 868, 870 disposed between the two force distribution systems 804, 806. Similarly, force distribution system 802 can be secured relative to force distribution system 804 by the bolts 854 with a plurality of friction reducing plates 876, 878 disposed therebetween to minimize friction between the two force distribution systems 802, 804.

The damping system 850 can include an anchor 894 disposed beneath the force distribution systems 802, 804, 806 and configured to secure the damping system 850 to the ground. The anchor 894 can be coupled to a post 884 by a bracket 890. The bracket 890 can include an aperture or bore 888 that is configured to align with an aperture 892 on the anchor and receive a fastener, for example, a bolt, pin, or threaded fastener therethrough to couple the anchor 894 with the bracket 890. The post 884 can extend from the bracket 890 through bores or apertures in the top plate 856, bottom plate 880, and slotted brackets 862, 870, 874, and a nut 852 can be used to secured the anchor 894 relative to the top plate 856. In this way, the damping system 850 couples the force distribution systems 802, 804, 806 relative to one another to cancel the forces received from the force distribution systems 802, 804, 806 and the anchor 894 couples the damping system 850 with the ground.

FIG. 22 schematically illustrates a perspective view of an embodiment of a foundation system 900 for a tower. In one embodiment the foundation system 900 is coupled to the lower section 943 of a folding tower, for example, a folding wind tower. The foundation system 900 includes three force distribution systems 904 a, 904 b, 904 c coupled to three tower legs 903 a, 903 b, 903 c of the lower section 943 of the folding tower. Each force distribution system 904 a, 904 b, 904 c can include at least one force distribution member 908 a, 908 b, 908 c that extend between anchors 917 a, 917 b, 917 c and a central anchor 914. The force absorbing members 908 a, 908 b, 908 c can include one or more friction reducers 919 a, 919 b, 919 c disposed therebetween. In one embodiment, the force distribution systems 904 a, 904 b, 904 c can be coupled to the central anchor 914 by a central anchor bracket 916. One or more friction reducers 915 can be disposed between the force distribution systems 904 a, 904 b, 904 c and the central anchor bracket 916. A damper 930 can be positioned between the central anchor bracket 916 and the friction reducer 915 to absorb vibrations from the folding wind tower. In some embodiments the damper 930 is made from a flexible material such as rubber, or a spring, such as a disc spring. Additionally, an optional anchor adapter 913 can be disposed between the central anchor bracket 916 and the central anchor 914. In some embodiments, a winch mechanism 907 can be coupled to an end of a force distribution system 904 c. As discussed in further detail below, the winch mechanism 907 can be used to rotate the lower section 943 relative to the foundation system 900 to raise the lower section.

In some embodiments, the foundation system 900 can include one or more braces 911 securing the force distribution systems 904 a, 904 b, 904 c relative to one another. In one embodiment, the system 900 can include a first brace 911 coupled to the first force distribution system 904 a and the second force distribution system 904 b, a second brace 911 coupled to the second force distribution system 904 b and the third force distribution system 904 c, and a third brace 911 coupled to the third force distribution system 904 c and the first force distribution system 904 a. The one or more optional braces 911 can provide several advantages, including, for example, providing torsional support for the foundation system 900 when the folding tower is subjected to seismic waves (e.g., providing torsional support during earthquakes) and securing the force distribution systems 904 a, 904 b, 904 c relative to one another to create a stronger foundation system 900. The additional torsional support and strength provided by one or more optional braces 911 disposed between force distribution systems 904 a, 904 b, 904 c can also be advantageous during the tower raising when the anchors 917 a, 917 b, 917 b are subject to substantial lateral forces that could cause the anchors 917 a, 917 b, 917 b to move horizontally relative to the ground.

FIG. 23 is a perspective view of an embodiment of a pulley lever system 920 that is coupled to a portion of an upper section 941 of a folding tower, for example, a folding wind tower. In one embodiment the pulley lever system 920 can include a pulley lever 927 that extends between a pulley 929 and a pulley bracket 922. The pulley 929 can be rotatably coupled to the pulley lever 927 by one or more fasteners 931, for example, a bolt. Similarly, the pulley lever 927 can be coupled to the pulley bracket 922 by one or more fasteners 925, for example, bolts. In some embodiments, the pulley bracket 922 includes a first section 921 a and a second section 921 b that is coupled to the first section 921 a by fasteners 925 with the pulley lever 927 therebetween. The pulley bracket 922 and/or pulley lever 927 can be coupled to a latch mechanism 923 that can be configured to create a latch connection between the upper section 941 of the folding tower and a lower section (not shown) of the folding tower. In some embodiments, the latch mechanism 923 can include one or more features present in the latch mechanism 700 schematically illustrated in FIG. 18.

As discussed above with reference to FIGS. 1-9, a flexible tension member (not shown) can be attached to a lever of an upper section of a folding tower to rotate the upper section relative to a lower section to position the folding tower in a raised configuration or position. The pulley lever system 920 can be coupled to the upper section 941 of a folding tower to rotate the upper section 941 relative to a lower section (not shown) and provides advantages over directly attaching a flexible tension member to the upper section 941. For example, the pulley lever system 920 can offset a flexible tension member (not shown) from the latch mechanism 923 such that the flexible tension member does not interfere with a latch connection. In one embodiment, a flexible tension member is guided through pulley 929 such that the flexible tension member is offset by the length of the pulley lever 927 from the latch mechanism 923. Additionally, in some embodiments, this offset can create a mechanical advantage and reduce the force required rotate the upper section 941 relative to a lower section (e.g., reduce the force required to raise the tower). Further, the pulley 929 can provide a mechanical advantage to reduce the force required to rotate the upper section 941 using a flexible tension member. In some embodiments where the forces required to raise an upper section of the folding tower are minimal, the pulley 929 is not used and the flexible tension member can be attached to the pulley lever 927 using standard fasteners.

FIG. 24 is a side elevation view of an embodiment of a folding tower system 940 including a folding tower 942. The folding tower 942 includes an upper section 941 and a lower section 943 that is rotatably coupled to the upper section 941 by a hinge 945. The upper section 941 is coupled to an extension 949 that is coupled to a friction reducing member 948. In some embodiments, the friction reducing member 948 comprises a wheel that is configured to roll on the ground surface. The friction reducing member 948 can be configured to reduce the frictional force between the upper section 941 and the ground when the upper section 941 is rotated relative to the lower section 943. The upper section 941 also includes a lever 922 that can be coupled to a flexible tension member (not shown) to rotate the upper section relative to the lower section. As discussed above, in some embodiments, the flexible tension member can be coupled to pulley lever system 920,

The lower section 943 of the folding tower 942 can be rotatably coupled to foundation system 900 by one or more hinges 912. A leverage boom 944 can extend from a lower portion of the lower section and a flexible tension member 947 can be guided over a distal end of the leverage boom 944 and coupled to a portion of the lower section 943. In this way, the flexible tension member 947 can be used to rotate the lower section 943 relative to the foundation system 900 (e.g., to raise the lower section 943).

A turbine offset system 950 extends from the lower section 943 of the tower 942. The turbine offset system 950 can offset the lower section 943 from the ground 946 such that the lower section 943 and the ground 946 form an acute angle therebetween. In this way, when the lower section 943 and upper section 941 of the tower 942 are lying on the ground, the lower section 941 and upper section 943 form an angle less than 180° therebetween. The angle between the lower section 941 and the upper section 943 caused by the offset system 950 can reduce the force required to rotate the lower section 941 relative to the upper section 943 because the lower section 941 is not horizontal with the ground surface 946. Additionally, when the lower section 941 is in an upright position and the upper section 943 has not been raised, the turbine offset system 950 prevents the upper section 943 from contacting the lower section 941. Similarly, when a turbine (not shown) or similar object is coupled to the distal end of the upper section 941, and the upper section 941 rests against the turbine offset system 950, the turbine will be offset from the lower section 943 (e.g., will not contact the lower section 943). Moreover, when the lower section 943 is raised and the upper section 941 is not raised, the turbine offset system 950 can be used to brace the upper section 941 relative to the lower section 943 in order to install or work on a turbine or another object coupled near the distal end of the upper section 941.

As shown in FIGS. 24 and 25, in some embodiments, the turbine offset 950 includes an offset brace 953 extending from the lower section 941 in a generally perpendicular direction, an offset diagonal brace 951 extending diagonally from the lower section 943, and an offset horizontal brace 957 coupled to the offset diagonal brace 951 and the offset brace 953. One or more additional members 958 a, 958 b can couple the offset brace 953, offset horizontal brace 957, and/or offset diagonal base 951 to an offset attachment structure 955 that is coupled to the lower section 941. Braces 953, 951 and members 958 a, 958 b can extend in other directions from the lower section 943. For example, in one embodiment, offset brace 953 can extend from the lower section 943 in a direction that is not perpendicular to the lower section 941. Additionally, the horizontal brace 957 can extend between the braces 953, 951 at an angle such that the brace 957 is not disposed horizontally

FIGS. 24 and 25 also schematically illustrate a flexible tension member 908 guided by pulley lever system 920 and coupled to a flexible tension member attachment structure 928 on the lower section 943. The other end of the flexible tension member 908 can be coupled to winch mechanism 907 disposed on the foundation system 900. In this configuration, the winch mechanism 907 can be used to raise and lower the upper section 941 relative to the foundation system 900 by shortening and lengthening the flexible tension member 908 between the upper section 941 and the foundation system 900. The turbine offset system 950 also can increase the mechanical advantage and lower the force required for the winch mechanism 907 to raise the upper section 941 after the lower section 943 is vertical by creating an angle between the lever 922 and the lower section 943 that provides more leverage.

FIG. 26 schematically illustrates another embodiment of a foundation system 1000 that can secure a folding tower (not shown) to a ground surface. The foundation system 1000 can include a plurality of force distribution systems 1002 a, 1002 b, 1002 c and each force distribution system can include one or more damping members 1004 a, 1004 b, 1004 c. One end of each of the force distribution systems 1002 a, 1002 b, 1002 c can be coupled to a clamp plate 1025 and the other end of each force distribution system 1002 a, 1002 b, 1002 c can be coupled to a hinge 1023 a, 1023 b, or leg plate 1013. The clamp plate 1025 can be coupled to an anchor adapter 1005 by a clamp fastener or bolt 1001. A flexible plate 1027 and force distribution systems 1002 a, 1002 b, 1002 c can be disposed between the anchor adapter 1005 and the clamp plate 1025. Braces 1007 can extend between force distribution systems 1002 a, 1002 b, 1002 c to provide torsional support thereto and to secure the force distribution systems 1002 a, 1002 b, 1002 c relative to one another. Hinges 1023 a, 1023 b can be coupled to the force distribution systems 1002 a, 1002 b, by various fasteners 1001, for example, bolts, spacers, and/or nuts. Similarly, leg plate 1013 can be coupled to force distribution system 1002 c by various fasteners 1001, for example, bolts, spacers, and/or nuts. Force distribution systems 1002 a, 1002 b, 1002 c can also be coupled to anchors 1021 a, 1021 c by one or more fasteners 1001, for example, bolts, spacers, and/or nuts.

Turning now to FIGS. 27-31, an embodiment of a guyed monopole folding tower 1200 is schematically illustrated. For ease of illustration, some of the FIGS. 27-31 omit certain features present in other of FIGS. 27-31. For example, lower guy wires 1280 a-d and upper guy wires 1270 a-d are only illustrated in FIGS. 30 and 31. The tower 1200 includes a lower section 1210 and an upper section 1212. The lower section 1210 is coupled to a lower hinge plate 1218 and the upper section 1212 is coupled to an upper hinge plate 1214. The upper hinge plate 1214 and the lower hinge plate 1212 are coupled together by a hinge knuckle 1216. In this way, the upper section 1212 can rotate relative to the lower section 1210 and the lower section 1210 can rotate relative to the upper section 1212. The upper hinge mechanism 1282 formed in part by the upper plate 1214, lower plate 1218, and hinge knuckle 1216 can also optionally include a hinge aperture 1220, hinge coupler 1222, and hinge clamp 1224.

The lower section 1210 can be coupled to an anchor 1306, for example a helical anchor. The helical anchor 1306 can include a plurality of helices 1308, 1310, 1312 configured to secure the anchor 1306 relative to the ground. The lower section 1210 can be rotatably coupled to the anchor 1306 by a base hinge 1302. In this way, the tower 1200 can be raised in more than one step. In one embodiment, the lower section 1210 can be rotated about the hinge 1302 relative to the ground to an upright or raised position and the upper section 1212 can be subsequently rotated about the upper hinge mechanism relative to the lower section 1210 to an upright or raised position such that the lower section 1210 and the upper section 1212 are substantially aligned. In some embodiments, one or more flexible tension members 1230, 1232, 1254 and a winch mechanism 1304 can be used to raise and/or lower the upper section 1212 and/or lower section 1210 of the tower 1200. In one embodiment, upper section 1212 can include a lever 1226, which in some embodiments is a steel tube, that can be used to manipulate the upper section 1212 and to rotate the upper section 1212 relative to the lower section 1210. In some embodiments a boom 1258, which can be a steel tube, can be attached at a first end substantially perpendicular to a first end of the lever 1226, and a flexible tension member 1230 can be attached at a first end to a boom bracket 1256 welded to a second end of the boom 1258, and at a second end can be attached to a second end 1228 of the lever 1226. A flexible tension member 1232 can be attached at a first end to the boom bracket 1256 using standard fasteners, and at a second end be attached to the upper section top 1234. The boom 1258 and flexible tension members 1230 and 1232 can provide support to the upper section 1212 during the raising and lowering of the upper section 1212.

As shown in FIG. 30, upper guy wires 1270 a-d can be used to stabilize the upper section 1212 and can be coupled to the ground and the upper section 1212. In some embodiments, lower guy wires 1280 a-d can be used to stabilize the lower section 1210 and can be coupled to the ground and the lower section 1210. In the illustrated embodiment, each of upper guy wires 1270 a-d are coupled to the ground at a location substantially coincident with one of the lower guy wires 1280 a-d, such that a pair of guy wires extends upward from each of four locations distributed symmetrically about the tower 1200. As can best be seen in the overhead view of FIG. 31, each of the pairs of guy wires thus extends through a vertically extending plane, and opposing pairs of guy wires may extend through the same vertically extending plane due to their substantially symmetrical positioning around the tower 1200. For example, the guy wires 1270 a,1280 a extend through a vertically extending guy wire plane 1292 a, which is substantially aligned with the vertically extending guy wire plane 1292 c through which guy wires 1270 a and 1280 a extend.

Certain of guy wires 1270 a-d or 1280 a-d may be in place during rotations of portions of the tower relative to one another to raise or lower said portions of the tower. For example, in particular embodiments, the lower guy wires 1280 a-d may be installed in place after the lower section 1210 has been rotated about the hinge 302 relative to the ground to an upright or raised position, but before the upper section 1212 is subsequently rotated about the upper hinge mechanism 1282 relative to the lower section 1210 to place the upper section 1212 in an upright or raised position. Thus, the lower guy wires 1280 a-d can provide stability to the structure during the subsequent raising of the upper section 1212 about the upper hinge mechanism 1282.

Because the lower guy wires 1280 a-d may be in place during the subsequent raising of the upper section 1212, and the upper section 1212 will itself rotate through a plane of rotation during the raising of the upper section 1212, the plane of rotation of the upper section 1212 may be angularly offset from the vertical planes through which the lower guy wires 1280 a-d extend. Still with respect to FIG. 31, it can be seen that a plane 1291 through which the upper portion 1212 of the tower will rotated is angularly offset by an angle θ from an adjacent vertical plane 1292 d through which guy wires 1270 d and 1280 d extend. Because the turbine 1290 may be installed on the upper section 1212 at the time of the rotation, the offset angle is sufficient to allow the turbine to pass by an installed guy wire (such as lower guy wire 1280 d) without contacting the installed guy wire. The necessary angle θ between the plane of rotation 1291 and the closest adjacent guy wire plane will depend on the size of the turbine and on the size and positioning of the tower components and the installed guy wire, but in certain embodiments may be more than 2°, and in further embodiments may be more than 5° or more than 10°.

In certain embodiments, the planes of rotation of both the upper and lower sections of the tower may be substantially aligned with one another. In other embodiments, a given pair of upper and lower guy wires may be secured to the ground at different locations, which may be radially or angularly offset from one another, and there may be greater or fewer numbers of upper or lower guy wires. In such an embodiment, the plane of rotation of a portion of the tower may be selected to be angularly offset from guy wire planes corresponding to those guy wires which may be installed at the time that the given portion tower is to be rotated.

The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the invention can be practiced in many ways. As is also stated above, it should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to including any specific characteristics of the features or aspects of the invention with which that terminology is associated. The scope of the invention should therefore be construed in accordance with the appended claims and any equivalents thereof. 

1. A foundation system for a folding tower having at least three legs, comprising: a plurality of anchors, the anchors comprising elongated members configured to penetrate into an underlying surface to secure the foundation system relative to the underlying surface; a centroid absorber; a plurality of force distribution members extending from the centroid absorber and configured to distribute forces applied to the tower, at least one force distribution member for each tower leg, the force distribution members distributing a first portion of said forces to the anchors, and a second portion of said forces to the centroid absorber, wherein a sum of the first and second portions equals a total force transferred by the tower to the anchors and the absorber; and a first hinge configured to be attached to at least one of the legs of the tower; a first leg mount attached to one of the force distribution members and disposed between the first hinge and said force distribution member.
 2. The foundation system of claim 1, further comprising a second hinge configured to be attached to at least one of the legs of the tower.
 3. The foundation system of claim 2, further comprising a second leg mount attached to one of the force distribution members and disposed between the second hinge and said force distribution member.
 4. The foundation system of claim 2, wherein the first hinge comprises a first axis of rotation, wherein the second hinge comprises a second axis of rotation, and wherein the first axis of rotation and the second axis of rotation are coaxial.
 5. The foundation system of claim 1, wherein the number of anchors is equal to or greater than the number of tower legs.
 6. The foundation system of claim 1 wherein the centroid absorber is configured to offset tensile and compressive forces transferred by the folding tower to the plurality of force distribution members.
 7. The foundation system of claim 6 wherein the centroid absorber dampens forces applied by the folding tower to the plurality of force distribution members.
 8. The foundation system of claim 1 wherein the force distribution members dampen forces applied by the folding tower to the plurality of force distribution members.
 9. A folding tower comprising: a hinged base portion; an anchor, wherein the hinged base portion is configured to rotate relative to the anchor; and a damping system, wherein the damping system couples the base portion to the anchor, the damping system comprising a lever bar having a first end and an opposite second end, wherein the base portion and anchor are coupled to the lever bar near the first end, a first energy storing element, wherein the first energy storing element is coupled to the lever bar near the second end, and a second energy storing element, wherein the second energy storing element is coupled to the lever bar near the second end, and wherein the second energy storing element extends from the lever bar in a direction that is generally opposite to a direction that the first energy storing element extends from the lever bar.
 10. The folding tower of claim 9, wherein the anchor and the second energy storing element engage a common ground surface.
 11. The folding tower of claim 9, wherein the base portion is hingedly coupled to the damping system.
 12. The folding tower of claim 10, further comprising a bracing member, wherein the bracing member is generally aligned with the lever bar, and wherein the bracing member is coupled to the base portion and to the first energy storing element.
 13. The folding tower of claim 9, wherein the first and second energy storing elements comprise springs.
 14. A foundation system for a folding tower, the foundation system comprising: a plurality of damping systems, wherein at least one damping system comprises a hinged leg mount; a base rigidly attached to an underlying surface; and a force distribution system attached to the base and configured to reduce loads applied to the base, wherein each of said plurality of damping systems is coupled to the force distribution system and to the base.
 15. The foundation system of claim 14, wherein each of said plurality of damping systems comprises a leg mount configured to support a leg of a folding tower.
 16. The foundation system of claim 15, wherein each leg mount is disposed on at least one force absorbing member.
 17. The foundation system of claim 16, wherein each damping system comprises a plurality of force absorbing members.
 18. The foundation system of claim 14, wherein at least one of the plurality of damping systems comprises a leg mount that is not hinged.
 19. The foundation system of claim 14, wherein two of the plurality of damping systems comprise hinged leg mounts, wherein each of the two hinged leg mounts include hinges, and wherein each of the two hinges is coaxially aligned with the other hinge.
 20. A folding tower comprising: a first portion; a second portion, wherein the first portion is configured to rotate relative to the second portion between at least a first position and a second position; a pivot, the pivot located between the first portion and the second portion, the pivot defining an axis of rotation for the first portion relative to the second portion, a lever, the lever including an elongated structure that is substantially collinear with the first portion; a boom, the boom including an elongated structure that is substantially perpendicular to the first portion; and at least one connector, the connector including a first end and a second end, the first end attached to the first portion, and the second end attached to the boom.
 21. The folding tower of claim 20, further comprising a second connector, the second connector including a first end a second end, the first end attached to the lever, and the second end attached to the boom.
 22. The folding tower of claim 21, wherein the first and second connectors are flexible tension members. 23-83. (canceled) 